A System and Method for Detecting, Demodulating, and Analyzing Drone RemoteID Signals

Abstract

The present invention relates to a system and method for detecting, demodulating, and analyzing UAV RemoteID signals. The host computer sends task instructions to the central control module through a network module for radio frequency data acquisition: the central control module controls the radio frequency receiving module to collect electromagnetic wave signals in a specified frequency band of the airspace environment, and performs low-noise amplification and filtering processing on the electromagnetic wave signals in the specified frequency band; for IQ data acquisition: the intermediate frequency acquisition module collects signals and performs mixing, filtering, and AD sampling processing; the collected IQ data is input into the baseband data processing module, and the baseband data processing module performs analysis and processing based on the UAV RemoteID signal detection algorithm, the UAV RemoteID signal demodulation algorithm, and the UAV RemoteID signal parsing algorithm; the operation results of the baseband signal processing module are transmitted to the host computer for display through the network transmission module. It can realize the supervision and analysis of RemoteID signals in long distance and non-standard frequency bands, with strong system stability and high accuracy of algorithm detection, demodulation, and analysis.

Description

Technical Field

[0001] The present invention belongs to the technical field of UAV signal processing, and particularly relates to a system and method for detecting, demodulating, and parsing UAV RemoteID signals. Background Art

[0002] Currently, the UAV technology in China has developed rapidly, and the safety supervision of UAVs has become an important issue. RemoteID (Remote Identification) is the core technology for UAV supervision, which requires UAVs to be remotely identifiable during flight. This technology allows UAV operators to broadcast their identity and location information to authorized services and airspace managers without revealing their physical location. The existing technologies for UAV RemoteID signals mainly achieve data broadcasting through radio signals (such as Bluetooth, Wi-Fi). There are differences in RemoteID standards in different countries and regions. Currently, the main RemoteID transmission modes for domestic UAVs are the following three: Bluetooth (4.x compatible) transmission mode, Bluetooth (5.0) long-range extended broadcast transmission mode, and Wi-Fi Beacon transmission mode.

[0003] For UAV RemoteID signals in the Wi-Fi Beacon transmission mode, the existing detection and parsing methods are mainly implemented based on hardware modules (Wi-Fi modules). The standard receiving and monitoring distance is usually only dozens of meters to hundreds of meters, which is difficult to meet the requirements of remote supervision of UAVs. Moreover, the hardware scalability is poor, and the ability to intercept and parse RemoteID signals in non-standard frequency bands is weak.

[0004] Therefore, how to improve the existing methods for detecting, demodulating, and parsing UAV RemoteID signals to achieve the supervision and analysis of RemoteID signals in long-distance and non-standard frequency bands, enhance the system stability, and improve the accuracy of algorithm detection, demodulation, and parsing is a technical problem that urgently needs to be solved at present. Summary of the Invention

[0005] The purpose of the present invention is to provide a system and method for detecting, demodulating, and parsing UAV RemoteID signals. By building a UAV RemoteID signal receiving system, the collected signals are detected, demodulated, and parsed for UAV RemoteID signals to achieve the supervision and analysis of RemoteID signals in long-distance and non-standard frequency bands, enhance the system stability, and improve the accuracy of algorithm detection, demodulation, and parsing.

[0006] To solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0007] A method for detecting, demodulating, and parsing UAV RemoteID signals includes the following steps:

[0008] S1: The host computer sends task instructions to the central control module through the network module;

[0009] S2: Perform radio frequency data acquisition: The central control module controls the radio frequency receiving module to collect electromagnetic wave signals in the specified frequency band of the airspace environment, and performs low-noise amplification and filtering processing on the electromagnetic wave signals in the specified frequency band;

[0010] S3: Perform IQ data acquisition: The intermediate frequency acquisition module collects signals and performs mixing, filtering, and AD sampling processing;

[0011] S4: Input the acquired IQ data into the baseband data processing module, and perform analysis and processing through the baseband data processing module based on the UAV RemoteID signal detection algorithm, UAV RemoteID signal demodulation algorithm, and UAV RemoteID signal parsing algorithm;

[0012] S5: Transmit the operation result of the baseband signal processing module to the host computer for display through the network transmission module.

[0013] Preferably, the specific process of performing low-noise amplification and filtering processing on the electromagnetic wave signals in the specified frequency band in step S2 is as follows:

[0014] S21: Use an impedance matching network to match the output impedance of the antenna with the input impedance of the low-noise amplifier;

[0015] S22: Use a low-noise amplifier to amplify the received signal, and use a band-pass filter with a passband of 2400 MHz to 2476 MHz or 5725 MHz to 5829 MHz h ( t ) to perform filtering processing on the amplified electromagnetic wave signal z ( t ) to obtain a signal y ( t );

[0016] Among them, the specific formula for filtering processing is as follows:

[0017] y ( t ) = z ( t ) * h ( t ).

[0018] Preferably, the specific process of the intermediate frequency acquisition module collecting signals and performing mixing, filtering, and AD sampling processing in step S3 is as follows:

[0019] S31: Use a mixer to mix the input signal y ( t ) with the local oscillator signalLO Perform a first mixing to generate an intermediate frequency signal IF 1;

[0020] S32: Use an intermediate frequency filter to filter out the spurious signals and noise generated during the mixing process, and mix the signal with the local oscillator signal LO Perform a second mixing to generate an intermediate frequency signal IF 2;

[0021] S33: At a sampling rate f s Sample and digitize the intermediate frequency signal IF 2 to obtain baseband IQ data with a sampling rate of f s and a length of N .

[0022] Preferably, the specific process of detecting the UAV RemoteID signal based on the UAV RemoteID signal detection algorithm in step S4 is as follows:

[0023] S41: Denote the collected baseband IQ complex signal samples as X ( n ), n = 0, 1, ···, N -2, N -1;

[0024] S42: With points as the step, T u being the effective symbol length of the UAV RemoteID signal, T u * f s points as the window length, perform a fast Fourier transform on the input samples based on the FFT algorithm, and use the channel energy detection algorithm to detect whether the IQ data contains the UAV RemoteID signal;

[0025] Among them, the specific formula of the channel energy detection algorithm is as follows:

[0026] F ( m ) = FFT ( X ( m ));

[0027] ;

[0028] Among them, K is a constant, and the empirical value is taken as 30;

[0029] S43: Judge dccheckAre the following conditions met:

[0030] dccheck ≥ th ;

[0031] in, th is the channel energy detection threshold, and the verification value is 15;

[0032] If satisfied, record the detection start index check index , go to the next step; if not satisfied, exit this test.

[0033] Preferably, the specific process of demodulating the drone RemoteID signal based on the drone RemoteID signal demodulation algorithm in step S4 is as follows:

[0034] S44: Perform OFDM symbol synchronization to detect the start index check inde 16* for the starting point f s IQ complex signal samples X ,by For stepping, For a single symbol length, a 9-symbol cross-correlation calculation is performed. The specific calculation formula is as follows:

[0035] ;

[0036] in, , ;

[0037] S45: Yes Perform a maximum value search, and the index of the maximum value position found is recorded as I max ;

[0038] S46: Estimating the frequency deviation. I max Starting point K IQ complex signal samples X ( k ), based on the cross-correlation of the two long training numbers, the carrier offset is calculated. The specific calculation formula is as follows:

[0039] ;

[0040] ;

[0041] S47: Perform frequency deviation calibration, and calculate the frequency offset based on the above formula Complex signal samples X Calibrate point by point. The specific calibration calculation formula is as follows:

[0042] ;

[0043] S48: Perform channel estimation, and perform 2-point FFT on the position data of two long training symbols of the calibrated samples T u * f s and calculate the channel amplitude and phase to obtain the channel calibration vector H , and the calculation formula is as follows:

[0044] ;

[0045] S49: Perform channel calibration, and perform symbol-by-symbol T u * f s point FFT demodulation, and calibrate the FFT result. The calibration formula is as follows:

[0046] .

[0047] Preferably, after step S49, perform channel processing on the calibrated demodulation data , and the specific process is as follows:

[0048] S50: Perform channel processing on the calibrated demodulation data , perform inverse mapping of the BPSK constellation diagram, and match the real and imaginary parts of the sequence F data to the nearest BPSK constellation point and use hard decision to restore the bit information;

[0049] S51: Perform deinterleaving processing on the restored bit information in a way of writing by row and reading by column;

[0050] S52: Perform (2,1,7) convolutional decoding on the deinterleaved bit information;

[0051] S53: Perform XOR descrambling processing on the bits after convolutional decoding and the scrambled bits to obtain the MAC layer frame bytes;

[0052] S54: Perform MAC layer frame processing, parse the fields of the MAC layer frame according to the frame format, and determine whether it is a WiFi-Beacon frame. If so, perform RemoteID message parsing processing; if not, exit this parsing.

[0053] Preferably, the specific process of performing RemoteID message parsing processing in step S54 is as follows:

[0054] Parse the valid part bits of the MAC layer frame body segment according to the RemoteID format to parse ID messages, position vector messages, operation description messages, system messages, and packaged messages.

[0055] In a second aspect, a system for detecting, demodulating, and parsing UAV RemoteID signals is provided to implement the method for detecting, demodulating, and parsing UAV RemoteID signals, including a 2.4GHz / 5.8GHz receiving antenna, a radio frequency receiving module, an intermediate frequency acquisition module, a clock module, a baseband signal processing module, a central control module, a network transmission module, and a host computer.

[0056] The 2.4GHz / 5.8GHz receiving antenna is used to acquire electromagnetic wave signals in the airspace.

[0057] The radio frequency receiving module is used to filter, frequency-convert, perform intermediate frequency processing, and perform automatic gain control on the received electromagnetic wave signals to obtain intermediate frequency signals, and the signals obtained after frequency conversion are secondarily frequency-converted signals.

[0058] The intermediate frequency acquisition module is used to mix, filter, and perform AD sampling on the intermediate frequency signals to obtain baseband IQ data.

[0059] The clock module is used to provide accurate clock signals to ensure the accurate operation of other modules.

[0060] The baseband signal processing module is used to perform signal processing on the baseband IQ data to implement the detection, demodulation, and parsing of UAV RemoteID signals, and send process data and result data.

[0061] The central control module is used to control the radio frequency receiving module, the intermediate frequency acquisition module, and the baseband signal processing module, and coordinate and manage each module.

[0062] The network transmission module is used to implement control instruction transmission and data transmission.

[0063] The host computer is used to display the content transmitted by the network transmission module.

[0064] Among them, the 2.4GHz / 5.8GHz receiving antenna is connected to the radio frequency receiving module; the radio frequency receiving module is connected to the intermediate frequency acquisition module; the intermediate frequency acquisition module is connected to the baseband signal processing module; the baseband signal processing module is connected to the network transmission module; the clock module is connected to the radio frequency receiving module, the intermediate frequency acquisition module, the baseband signal processing module, the network transmission module, and the central control module; the central control module is connected to the radio frequency receiving module, the intermediate frequency acquisition module, the baseband signal processing module, and the network transmission module.

[0065] The beneficial effects of the present invention include:

[0066] The system and method for detecting, demodulating and analyzing the RemoteID signal of an unmanned aerial vehicle provided by the present invention, the host computer sends task instructions to the central control module through the network module for radio frequency data acquisition: the central control module controls the radio frequency receiving module to collect the electromagnetic wave signals in the specified frequency band of the airspace environment, and performs low-noise amplification and filtering processing on the electromagnetic wave signals in the specified frequency band; for IQ data acquisition: the intermediate frequency acquisition module collects signals and performs mixing, filtering and AD sampling processing; input the collected IQ data into the baseband data processing module, and perform analysis and processing through the baseband data processing module based on the unmanned aerial vehicle RemoteID signal detection algorithm, the unmanned aerial vehicle RemoteID signal demodulation algorithm, and the unmanned aerial vehicle RemoteID signal parsing algorithm; transmit the operation result of the baseband signal processing module to the host computer for display through the network transmission module. Using the signal receiving system, the RemoteID signal of the unmanned aerial vehicle is collected, and the unmanned aerial vehicle RemoteID signal detection algorithm is used to judge whether the signal contains the RemoteID signal. If it contains, the demodulation algorithm is used for demodulation, and finally the RemoteID signal parsing algorithm is used for parsing, realizing the supervision and analysis of the RemoteID signal in the long distance and non-standard frequency band, effectively enhancing the system stability, and improving the detection, demodulation and parsing accuracy of the algorithm. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 It is a schematic structural diagram of the system for detecting, demodulating and analyzing the RemoteID signal of the unmanned aerial vehicle of the present invention.

[0068] Figure 2 It is a schematic flow diagram of the method for detecting, demodulating and analyzing the RemoteID signal of the unmanned aerial vehicle of the present invention.

[0069] Figure 3 It is a schematic flow diagram of the channel processing of the present invention.

[0070] Figure 4 It is a schematic flow diagram of the RemoteID message parsing of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0071] The following further elaborates on the present invention in conjunction with the attached Figures 1 to 4 for a more detailed description:

[0072] Embodiment 1

[0073] Referring to the attached Figure 1 As shown, a method for detecting, demodulating and analyzing the RemoteID signal of an unmanned aerial vehicle includes the following steps:

[0074] S1: The host computer sends task instructions to the central control module through the network module;

[0075] S2: Perform RF data acquisition: The central control module controls the RF receiving module to collect electromagnetic wave signals in the specified frequency band of the airspace environment, and performs low-noise amplification and filtering on the electromagnetic wave signals in the specified frequency band;

[0076] S3: Perform IQ data acquisition: The intermediate frequency acquisition module collects signals and performs mixing, filtering, and AD sampling;

[0077] S4: Input the acquired IQ data into the baseband data processing module, and perform analysis and processing through the baseband data processing module based on the UAV RemoteID signal detection algorithm, UAV RemoteID signal demodulation algorithm, and UAV RemoteID signal parsing algorithm;

[0078] S5: Transmit the operation result of the baseband signal processing module to the host computer for display through the network transmission module.

[0079] In this embodiment, the host computer sends a task instruction to the central control module through the network module. The central control module controls the RF receiving module to collect electromagnetic wave signals in the specified frequency band (2.4 GHz / 5.8 GHz) of the airspace environment, and performs low-noise amplification and filtering on the electromagnetic wave signals in the specified frequency band; perform IQ data acquisition: the intermediate frequency acquisition module collects signals and performs mixing, filtering, and AD sampling; input the acquired IQ data into the baseband data processing module, and perform analysis and processing through the baseband data processing module based on the UAV RemoteID signal detection algorithm, UAV RemoteID signal demodulation algorithm, and UAV RemoteID signal parsing algorithm; transmit the operation result of the baseband signal processing module to the host computer for display through the network transmission module. With the signal receiving system, the UAV RemoteID signal acquisition is realized. The UAV RemoteID signal detection algorithm is used to judge whether the signal contains the RemoteID signal. If it contains, the demodulation algorithm is used for demodulation, and finally the RemoteID signal parsing algorithm is used for parsing, realizing the supervision and analysis of the RemoteID signal in the long distance and non-standard frequency band, effectively enhancing the system stability, and improving the detection, demodulation, and parsing accuracy of the algorithm.

[0080] Embodiment 2

[0081] Based on Embodiment 1, the specific process of performing low-noise amplification and filtering on the electromagnetic wave signals in the specified frequency band in step S2 is as follows:

[0082] S21: Use an impedance matching network to match the output impedance of the antenna with the input impedance of the low-noise amplifier;

[0083] S22: Amplify the received signal using a low-noise amplifier and filter it with a band-pass filter having a passband of 2400 MHz to 2476 MHz or 5725 MHz to 5829 MHz h ( t ) for the amplified electromagnetic wave signal z ( t ) to obtain a signal y ( t );

[0084] Among them, the specific formula for the filtering process is as follows:

[0085] y ( t ) = z ( t ) * h ( t ).

[0086] In step S3, the specific process of the intermediate-frequency acquisition module for signal acquisition, mixing, filtering, and AD sampling is as follows:

[0087] S31: Use a mixer to mix the input signal y ( t ) with the local oscillator signal LO 1 for the first time to generate an intermediate-frequency signal IF 1;

[0088] S32: Use an intermediate-frequency filter to filter out the spurious signals and noise generated during the mixing process, and mix the signal with the local oscillator signal LO 2 for the second time to generate an intermediate-frequency signal IF 2;

[0089] S33: Digitally A / D sample the intermediate-frequency signal f s 2 at a sampling rate to obtain baseband IQ data with a sampling rate of IF 2 and a length of f s . N Example 3

[0090] Based on Example 1 or Example 2, the specific process of detecting the UAV RemoteID signal in step S4 using the UAV RemoteID signal detection algorithm is as follows:

[0091] S41: Denote the collected baseband IQ complex signal samples as

[0092] ( X ) n = 0, 1, ···, n = 0, 1, ···, N -2, N-1;

[0093] S42: With points as the step, T u is the effective symbol length of the drone RemoteID signal, T u * f s points as the window length, perform a fast Fourier transform on the input samples based on the FFT algorithm, and use the channel energy detection algorithm to detect whether the IQ data contains the drone RemoteID signal;

[0094] Among them, the specific formula of the channel energy detection algorithm is as follows:

[0095] F ( m ) = FFT ( X ( m ));

[0096] ;

[0097] Among them, K is a constant, and the empirical value is taken as 30;

[0098] S43: Judge whether dccheck meets the following conditions:

[0099] dccheck ≥ th ;

[0100] Among them, th is the channel energy detection threshold, and the empirical value is taken as 15;

[0101] If it is satisfied, record the detection start index check index , and go to the next step; if it is not satisfied, exit this detection.

[0102] The specific process of demodulating the drone RemoteID signal based on the drone RemoteID signal demodulation algorithm in step S4 is as follows:

[0103] S44: Perform OFDM symbol synchronization, and perform 9-symbol cross-correlation calculation on 16 * check inde IQ complex signal samples starting from f s with X as the step and as the single symbol length. The specific calculation formula is as follows:

[0104] ;​

[0105] Among them, , ;

[0106] S45: Perform a maximum value search on , and record the index of the position of the maximum value found as I max ;

[0107] S46: Perform frequency offset estimation. Using I max as the starting point, for K IQ complex signal samples X ( k ), perform cross-correlation based on 2 long training sequence numbers to calculate the carrier offset. The specific calculation formula is as follows:

[0108] ;

[0109] ;

[0110] S47: Perform frequency offset calibration. Based on the frequency offset calculated by the above formula, calibrate each point of the complex signal sample X . The specific calibration calculation formula is as follows:

[0111] ;

[0112] S48: Perform channel estimation. Perform on the data at the positions of 2 long training symbols of the calibrated sample T u * f s point FFT, and calculate the channel amplitude and phase to obtain the channel calibration vector H . The calculation formula is as follows:

[0113] ;

[0114] S49: Perform channel calibration. For the calibrated sample , perform T u * f s point FFT demodulation for each symbol, and calibrate the FFT result. The calibration formula is as follows:

[0115] .

[0116] After step S49, perform channel processing on the calibrated demodulated data . The specific process is as follows:

[0117] S50: For the calibrated demodulation data perform channel processing, inverse mapping of the BPSK constellation diagram, and based on the real part and imaginary part of the sequence F data, match the nearest BPSK constellation point and use hard decision to restore the bit information;

[0118] S51: Perform deinterleaving processing on the restored bit information by writing row by row and reading column by column;

[0119] S52: Perform (2,1,7) convolutional decoding on the deinterleaved bit information;

[0120] S53: Perform XOR descrambling on the bits after convolutional decoding and the scrambled bits to obtain the MAC layer frame bytes;

[0121] S54: Perform MAC layer frame processing, parse the fields of the MAC layer frame according to the frame format, and determine whether it is a WiFi-Beacon frame. If so, perform RemoteID message parsing processing; if not, exit the current parsing.

[0122] Among them, the specific process of performing RemoteID message parsing processing in step S54 is as follows:

[0123] Canonically parse the bits of the valid part of the MAC layer frame body segment according to the RemoteID format, and parse the ID message, position vector message, operation description message, system message, and packaging message.

[0124] A system for detecting, demodulating, and parsing UAV RemoteID signals, used to implement the method for detecting, demodulating, and parsing UAV RemoteID signals, includes a 2.4GHz / 5.8GHz receiving antenna, a radio frequency receiving module, an intermediate frequency acquisition module, a clock module, a baseband signal processing module, a central control module, a network transmission module, and a host computer.

[0125] The 2.4GHz / 5.8GHz receiving antenna is used to acquire electromagnetic wave signals in the airspace. The radio frequency receiving module is used to filter, frequency convert, perform intermediate frequency processing, and automatic gain control on the received electromagnetic wave signals to obtain intermediate frequency signals, and the signal obtained after frequency conversion is a second-stage frequency conversion signal. The intermediate frequency acquisition module is used to mix, filter, and perform AD sampling on the intermediate frequency signals to obtain baseband IQ data. The clock module is used to provide accurate clock signals to ensure the accurate operation of other modules. The baseband signal processing module is used to perform signal processing on the baseband IQ data to detect, demodulate, and analyze the RemoteID signals of the unmanned aerial vehicle, and send process data and result data. The central control module is used to control the radio frequency receiving module, the intermediate frequency acquisition module, and the baseband signal processing module, coordinate and manage each module. The network transmission module is used to implement the transmission of control instructions and data. The upper computer is used to display the content transmitted by the network transmission module.

[0126] The 2.4GHz / 5.8GHz receiving antenna is connected to the radio frequency receiving module, the radio frequency receiving module is connected to the intermediate frequency acquisition module, the intermediate frequency acquisition module is connected to the baseband signal processing module, the baseband signal processing module is connected to the network transmission module, and the clock module is connected to the radio frequency receiving module, the intermediate frequency acquisition module, the baseband signal processing module, the network transmission module, and the central control module; the central control module is connected to the radio frequency receiving module, the intermediate frequency acquisition module, the baseband signal processing module, and the network transmission module.

[0127] In summary, for the system and method for detecting, demodulating, and analyzing the RemoteID signals of the unmanned aerial vehicle provided by the present invention, the upper computer sends task instructions to the central control module through the network module. The central control module controls the radio frequency receiving module to collect electromagnetic wave signals in the specified frequency band of the airspace environment, and performs low-noise amplification and filtering processing on the electromagnetic wave signals in the specified frequency band; perform IQ data acquisition: the intermediate frequency acquisition module collects signals and performs mixing, filtering, and AD sampling processing; input the collected IQ data into the baseband data processing module for analysis and processing through the baseband data processing module; transmit the operation result of the baseband signal processing module to the upper computer for display through the network transmission module. The signal receiving system realizes the acquisition of the RemoteID signals of the unmanned aerial vehicle, uses the RemoteID signal detection algorithm of the unmanned aerial vehicle to judge whether the signal contains the RemoteID signal. If it contains, the demodulation algorithm is used for demodulation, and finally the RemoteID signal parsing algorithm is used for parsing. The above process realizes the supervision and analysis of the RemoteID signals in the long distance and non-standard frequency band, effectively enhances the system stability, and improves the accuracy of algorithm detection, demodulation, and parsing.

Claims

1. A method for detecting, demodulating, and parsing RemoteID signals of an unmanned aerial vehicle, characterized in that, It includes the following steps: S1: The host computer sends a task instruction to the central control module through the network module; S2: Perform radio frequency data acquisition: The central control module controls the radio frequency receiving module to collect electromagnetic wave signals in the specified frequency band of the airspace environment, and performs low-noise amplification and filtering processing on the electromagnetic wave signals in the specified frequency band; S3: Perform IQ data acquisition: The intermediate frequency acquisition module collects signals and performs mixing, filtering, and AD sampling processing; S4: Input the collected IQ data into the baseband data processing module, and perform analysis and processing through the baseband data processing module based on the UAV RemoteID signal detection algorithm, UAV RemoteID signal demodulation algorithm, and UAV RemoteID signal parsing algorithm; S5: Transmit the operation result of the baseband signal processing module to the host computer for display through the network transmission module; The specific process of the intermediate frequency acquisition module collecting signals, performing mixing, filtering, and AD sampling processing in step S3 is as follows: S31: Use a mixer to mix the input signal y ( t ) with the local oscillator signal LO 1 for one-time mixing to generate an intermediate frequency signal IF 1; S32: Use an intermediate frequency filter to filter out the spurious signals and noise generated during the mixing process, and mix the signal with the local oscillator signal LO 2 for secondary mixing to generate an intermediate frequency signal IF 2; S33: At a sampling rate f s perform A / D sampling and digitization on the intermediate frequency signal IF 2 to obtain baseband IQ data with a sampling rate of f s and a length of N ; The specific process of detecting the UAV RemoteID signal based on the UAV RemoteID signal detection algorithm in step S4 is as follows: S41: Denote the collected baseband IQ complex signal samples as X ( n ) n = 0, 1, ···, N -2, N -1; S42: Using T u · fs / two points as the step, T u which is the effective symbol length of the UAV RemoteID signal, T u · fs using this point as the window length, performing a fast Fourier transform on the input samples based on the FFT algorithm, and using the channel energy detection algorithm to detect whether the IQ data contains the UAV RemoteID signal; Among them, the specific formula of the channel energy detection algorithm is as follows: F ( m )= FFT ( X ( m ))； ； Among them, K is a constant; S43: Determine dccheck whether the following conditions are met: dccheck≥th ； Among them, th is the channel energy detection threshold, and the verification value is taken as 15; If satisfied, record the detection start index check index , go to the next step; if not satisfied, exit this detection; The specific process of demodulating the UAV RemoteID signal based on the UAV RemoteID signal demodulation algorithm in step S4 is as follows: S44: Perform OFDM symbol synchronization and detect the starting index check inde as the starting point for 16 f s IQ complex signal samples X , and T u · fs / with a step of 8, T u · fs / a single symbol length of 4, perform 9-symbol cross-correlation calculation, and the specific calculation formula is as follows: ； wherein, i ∈ [0, 16 fs , l= T u · fs / 4; S45: For perform a maximum value search, and record the index of the maximum value position found as I max ; S46: Perform frequency deviation estimation starting from I max as the starting point K IQ complex signal samples X ( k ), perform cross-correlation based on 2 long training sequence numbers, calculate the carrier offset, and the specific calculation formula is as follows: ； ； S47: Perform frequency deviation calibration and calculate the frequency offset based on the above formula. For the complex signal samples X Perform calibration point by point, and the specific calibration calculation formula is as follows: ； S48: Perform channel estimation on the calibrated samples for the position data of two long training symbols T u · f s perform point FFT, and calculate the channel amplitude and phase to obtain the channel calibration vector H , and the calculation formula is as follows: ； S49: Perform channel calibration on the calibrated samples , and perform T u · f s point FFT demodulation, calibrate the FFT result, and the calibration formula is as follows: 。 2. The method for detecting, demodulating and analyzing the RemoteID signal of an unmanned aerial vehicle according to claim 1, wherein The specific process of performing low-noise amplification and filtering processing on the electromagnetic wave signals in the specified frequency band in step S2 is as follows: S21: Use an impedance matching network to match the output impedance of the antenna with the input impedance of the low-noise amplifier; S22: Amplify the received signal using a low-noise amplifier and filter the amplified electromagnetic wave signal with a band-pass filter having a passband of 2400 MHz to 2476 MHz or 5725 MHz to 5829 MHz h ( t ) for the amplified electromagnetic wave signal z ( t ) to obtain a signal y ( t ); Among them, the specific formula of the filtering processing is as follows: y ( t )= z ( t )· h ( t )。 3. A method for detecting, demodulating, and analyzing the RemoteID signal of an unmanned aerial vehicle according to claim 1, characterized in that, After step S49, for the calibrated demodulation data perform channel processing. The specific process is as follows: S50: For the calibrated demodulation data perform channel processing, inverse mapping of the BPSK constellation diagram, and according to the sequence F the real and imaginary parts of the data, match the nearest BPSK constellation points and use hard decision to restore the bit information; S51: Perform deinterleaving processing on the restored bit information by writing by row and reading by column; S52: Perform (2,1,7) convolutional decoding on the deinterleaved bit information; S53: Perform exclusive OR descrambling processing on the bits after convolutional decoding and the scrambled bits to obtain the MAC layer frame bytes; S54: Perform MAC layer frame processing, parse the MAC layer frame according to the frame format fields, and determine whether it is a WiFi-Beacon frame. If so, perform RemoteID message parsing processing; if not, exit the current parsing.

4. A method for detecting, demodulating, and analyzing the RemoteID signal of an unmanned aerial vehicle according to claim 2, characterized in that, The specific process of performing RemoteID message parsing processing in step S54 is as follows: Parse the valid part bits of the MAC layer frame body segment according to the RemoteID format to parse the ID message, position vector message, operation description message, system message, and packaged message.

5. A system for detecting, demodulating, and parsing UAV RemoteID signals, which is used to implement the method for detecting, demodulating, and parsing UAV RemoteID signals described in any one of claims 1-4, characterized in that, It includes a 2.4GHz / 5.8GHz receiving antenna, a radio frequency receiving module, an intermediate frequency acquisition module, a clock module, a baseband signal processing module, a central control module, a network transmission module, and a host computer; The 2.4GHz / 5.8GHz receiving antenna is used to obtain airspace electromagnetic wave signals; The radio frequency receiving module is used to filter, frequency-convert, perform intermediate frequency processing, and perform automatic gain control on the received electromagnetic wave signal to obtain an intermediate frequency signal, and the signal obtained after frequency conversion is a second-stage frequency-converted signal; The intermediate frequency acquisition module is used to mix, filter, and perform AD sampling on the intermediate frequency signal to obtain baseband IQ data; The clock module is used to provide an accurate clock signal to ensure the accurate operation of other modules; The baseband signal processing module is used to process the baseband IQ data, detect, demodulate, and analyze the UAV RemoteID signal, and transmit the process data and result data; The central control module is used to control the radio frequency receiving module, the intermediate frequency acquisition module, and the baseband signal processing module, and coordinate and manage each module; The network transmission module is used to implement control instruction transmission and data transmission; The upper computer is used to display the content transmitted by the network transmission module; Among them, the 2.4GHz / 5.8GHz receiving antenna is connected to the radio frequency receiving module; the radio frequency receiving module is connected to the intermediate frequency acquisition module; The intermediate frequency acquisition module is connected to the baseband signal processing module; the baseband signal processing module is connected to the network transmission module; the clock module is connected to the radio frequency receiving module, the intermediate frequency acquisition module, the baseband signal processing module, the network transmission module, and the central control module; the central control module is connected to the radio frequency receiving module, the intermediate frequency acquisition module, the baseband signal processing module, and the network transmission module.

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